Marks & Spencer is introducing packs into its Delicatessen Food Range utilising Virtuweld patented technology developed by Mister Blister, which claims that, until now, clamshell or hinged packs have proved "extremely difficult to tamper-proof" without the use of welding, expensive shrink collars or additional labelling.

Launched two years ago, Virtuweld is said to have been “extremely successful” in the non-food market where it “enables manufacturers to market products in packs that have the appearance and security of welded packs without the need for any secondary sealing and with many other benefits”.

Gary Briscoe, managing director of Mister Blister, comments: “Marks & Spencer had already decided what they were looking for and Virtuweld quite simply met their list of criteria. Nevertheless, we are very grateful for their assistance in further developing the Virtuweld concept to meet the unique requirements of the food industry.”